The present invention relates to a tractor for use in civil engineering, construction and the like, which tractor carries work implements at the front and the back thereof and operation units associated with the respective work implements and disposed at different vertical planes, one in front of the driver's seat and the other behind it. More particularly, the invention relates to a driver's seat mounting structure adapted to change the driver's seat between a forward facing position and a rearward facing position.
In the case where the front implement is shovel means and the rear implement is backhoe means, for example, the two implements operate differently and the operation unit for the backhoe means is disposed at a higher plane than the operation unit for the shovel means, to enable the driver to have a good view of the work being done by each of the implements. In other words, when working the backhoe means, the operator has to look down from a relatively high position as the place of ground engagement is close to the tractor.
Therefore, when the driver's seat is set in position facing the operation unit for whichever work implement to be worked, it is necessary to bring the seat to the position best suited for manipulation of the operation unit, that is to say a position at the right height and having the right space between the seat and the operation unit.
In satisfying the above conditions for the seat position, the provision of the right space between the seat and each of the units is a difficult question as far as a small size tractor is concerned. A small tractor can hardly afford a large work space for the driver, especially in the longitudinal direction of its body.
In order to solve this problem, various seat mounting structures have been employed in conventional practice. One example of the conventional art sets the swivelling axis of the driver's seat at a front portion thereof to obtain a good distance from each of the operation units, and changes the vertical plane of the seat by means of a hydraulic system or a gearing mechanism.
However, such conventional art generally has a disadvantage of complication in constuction and in changing the position of the seat.